34 research outputs found
Modified screen-printed carbon electrodes application for protein tumor markers determination
Screen-printed carbon electrodes were modified with gold nanoparticles bound with DNA-aptamers by two different methods. Aptamers can selectively bind protein tumor markers from the blood plasma. The electrodes were tested. Signals obtained via squire-wavy voltammetry from modified electrodes covered with blood plasma of the healthy donors and donors with lung cancer can be distinguished
Analysis of volume and topography of adipose tissue in the trunk: Results of MRI of 11,141 participants in the German National Cohort
This research addresses the assessment of adipose tissue (AT) and spatial distribution of visceral (VAT) and subcutaneous fat (SAT) in the trunk from standardized magnetic resonance imaging at 3 T, thereby demonstrating the feasibility of deep learning (DL)-based image segmentation in a large population-based cohort in Germany (five sites). Volume and distribution of AT play an essential role in the pathogenesis of insulin resistance, a risk factor of developing metabolic/cardiovascular diseases. Cross-validated training of the DL-segmentation model led to a mean Dice similarity coefficient of >0.94, corresponding to a mean absolute volume deviation of about 22 ml. SAT is significantly increased in women compared to men, whereas VAT is increased in males. Spatial distribution shows age- and body mass index-related displacements. DL-based image segmentation provides robust and fast quantification of AT (≈15 s per dataset versus 3 to 4 hours for manual processing) and assessment of its spatial distribution from magnetic resonance images in large cohort studies
Better together: data harmonization and cross-study analysis of abdominal MRI data from UK Biobank and the German National Cohort
OBJECTIVES: The UK Biobank (UKBB) and German National Cohort (NAKO) are among the largest cohort studies, capturing a wide range of health-related data from the general population, including comprehensive magnetic resonance imaging (MRI) examinations. The purpose of this study was to demonstrate how MRI data from these large-scale studies can be jointly analyzed and to derive comprehensive quantitative image-based phenotypes across the general adult population. MATERIALS AND METHODS: Image-derived features of abdominal organs (volumes of liver, spleen, kidneys, and pancreas; volumes of kidney hilum adipose tissue; and fat fractions of liver and pancreas) were extracted from T1-weighted Dixon MRI data of 17,996 participants of UKBB and NAKO based on quality-controlled deep learning generated organ segmentations. To enable valid cross-study analysis, we first analyzed the data generating process using methods of causal discovery. We subsequently harmonized data from UKBB and NAKO using the ComBat approach for batch effect correction. We finally performed quantile regression on harmonized data across studies providing quantitative models for the variation of image-derived features stratified for sex and dependent on age, height, and weight. RESULTS: Data from 8791 UKBB participants (49.9% female; age, 63 ± 7.5 years) and 9205 NAKO participants (49.1% female, age: 51.8 ± 11.4 years) were analyzed. Analysis of the data generating process revealed direct effects of age, sex, height, weight, and the data source (UKBB vs NAKO) on image-derived features. Correction of data source-related effects resulted in markedly improved alignment of image-derived features between UKBB and NAKO. Cross-study analysis on harmonized data revealed comprehensive quantitative models for the phenotypic variation of abdominal organs across the general adult population. CONCLUSIONS: Cross-study analysis of MRI data from UKBB and NAKO as proposed in this work can be helpful for future joint data analyses across cohorts linking genetic, environmental, and behavioral risk factors to MRI-derived phenotypes and provide reference values for clinical diagnostics
Susceptibility to chronic mucus hypersecretion, a genome wide association study
Background: Chronic mucus hypersecretion (CMH) is associated with an increased frequency of respiratory infections, excess lung function decline, and increased hospitalisation and mortality rates in the general population. It is associated with smoking, but it is unknown why only a minority of smokers develops CMH. A plausible explanation for this phenomenon is a predisposing genetic constitution. Therefore, we performed a genome wide association (GWA) study of CMH in Caucasian populations. Methods: GWA analysis was performed in the NELSON-study using the Illumina 610 array, followed by replication and meta-analysis in 11 additional cohorts. In total 2,704 subjects with, and 7,624 subjects without CMH were included, all current or former heavy smokers (≥20 pack-years). Additional studies were performed to test the functional relevance of the most significant single nucleotide polymorphism (SNP). Results: A strong association with CMH, consistent across all cohorts, was observed with rs6577641 (p = 4.25x10-6, OR = 1.17), located in intron 9 of the special AT-rich sequence-binding protein 1 locus (SATB1) on chromosome 3. The risk allele (G) was associated with higher mRNA expression of SATB1 (4.3x10 -9) in lung tissue. Presence of CMH was associated with increased SATB1 mRNA expression in bronchial biopsies from COPD patients. SATB1 expression was induced during differentiation of primary human bronchial epithelial cells in culture. Conclusions: Our findings, that SNP rs6577641 is associated with CMH in multiple cohorts and is a cis-eQTL for SATB1, together with our additional observation that SATB1 expression increases during epithelial differentiation provide suggestive evidence that SATB1 is a gene that affects CMH
Supplementary Material for: Locoregional Therapies of Cholangiocarcinoma
Background: Cholangiocarcinoma (CC) is the second
most primary liver malignancy with increasing incidence
in Western countries. Currently, surgical R0 resection is
regarded as the only potentially curative treatment. The
results of systemic chemotherapy and best supportive
care (BSC) in patients with metastatic disease are often
disappointing in regard to toxicity, oncologic efficacy,
and overall survival. In current practice, the use of different
locoregional therapies is increasingly more accepted.
Methods: A review of the literature on locoregional therapies
for intrahepatic cholangiocarcinoma (ICC) was undertaken.
Results: There are no prospective randomized
controlled trials. For localized ICC, either primary or recurrent,
radiofrequency ablation (RFA) is by far the most
commonly used thermal ablation modality. Thereby, a
systematic review and meta-analysis reports major complication
in 3.8% as well as 1-, 3-, and 5-year overall survival
rates of 82, 47, and 24%, respectively. In selected
patients (e.g. with a tumor diameter of ≤3 cm), oncologic
efficacy and survival after RFA are comparable with surgical
resection. For diffuse ICC, different transarterial
therapies, either chemotherapy-based (hepatic artery infusion
(HAI), transarterial chemoembolization (TACE)) or
radiotherapy-based (transarterial radioembolization
(TARE)), show extremely promising results. With regard
to controlled trials (transarterial therapy versus systemic
chemotherapy, BSC or no treatment), tumor control is
virtually always better for transarterial therapies and very often accompanied by a dramatic survival benefit
and improvement of quality of life. Of note, the latter is
the case not only for patients without extrahepatic metastatic
disease but also for those with liver-dominant extrahepatic
metastatic disease. There are other locoregional
therapies such as microwave ablation, irreversible
electroporation, and chemosaturation; however, the current
data support their use only in controlled trials or as
last-line therapy. Conclusion: Dedicated locoregional
therapies are commonly used for primary and recurrent
ICC as well as liver-only and liver-dominant extrahepatic
metastatic disease. Currently, the best evidence and
most promising results are available for RFA, HAI, TACE,
and TARE. In cohort studies, the overall survival rates
are similar to those obtained with surgery or systemic
therapies. Prospective randomized controlled trials are
warranted to compare safety and efficacy between different
surgical, interventional, and systemic therapies, as
well as their combinations
Niedrigdosis-Mehrzeilendetektor-CT mit niedrigen Röhrenspannungen und iterativer Bildrekonstruktion: wo liegt die Grenze diagnostischer Sicherheit in der Thoraxbildgebung?
Changes of prostate gland volume with and without androgen deprivation after intensity modulated radiotherapy - A follow-up study.
Item does not contain fulltextBACKGROUND AND PURPOSE: The shrinking effect of androgen deprivation therapy (ADT) on prostate volume is a known finding, but data on volume changes during radiotherapy are inconsistent. We examined patients with and without ADT undergoing intensity modulated radiotherapy (IMRT) and performed follow-up examinations to study volume changes before and after radiotherapy. METHODS AND MATERIALS: Prostate volumes between planning magnetic resonance imaging (MRI) and last available follow-up MRI were retrospectively determined in 39 patients. Median time interval between first and last MRI was 233days (range 126-813). Two observers performed volume measurements in consensus and were blind to the timing of MRI. Volume changes over MRI were determined using the ellipsoid formula. Data of patients with and without ADT were compared by a linear mixed model. RESULTS: Of 39 patients, 22 had ADT with a median duration of 5months (range 1-24). ADT patients showed lower prostate volume throughout the study period (-28% to 38%). Although individual shrinking effect was highly variable, patients treated with IMRT but without ADT showed a significantly larger volume reduction (26.1%) than patients with ADT (12.9%, p<0.05). CONCLUSIONS: Patients undergoing IMRT show definite prostate shrinkage. The rate is slowed down after 6months in both groups, whereas the volume reduction is significantly larger in patients without ADT. Nevertheless there is no adding effect of ADT+IMRT vs. IMRT alone
Lung cancer screening white paper: a slippery step forward?
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